In the animal kingdom, we often don’t tend to think too much about male mate choice, the choice that the males have over the females they mate with. This is mostly because…well we basically think that males will hump anything that looks vaguely like a female. Or even that DOESN’T look vaguely like a female. Case in point:
…maybe it’s just turtles?
But it turns out that males may in fact exercise a little more choice than we give them credit for. When the odds of finding a female are low (poor turtles), it’s every male for himself, but when there are plenty of females around, the females have very different reproductive capacities, or the males themselves have to give up a lot to mate successfully, choice will happen. Male animals discriminate between females based on things like body size and mass, previous fertility, and of course, ornamentation.
But the amount of choice the male makes can vary a lot depending on things like the social status of the males or environmental context. So the hypothesis is that males (especially males who have the opportunity to mate a LOT) will adjust, not who they mate with, but the quality of their ejaculate. By adjusting the quality of their ejaculate, males could maybe decide where to blow their wad, so to speak (yeah, I went there), and also put the best ejaculate where they need to compete against other males.
But how do we TEST the things which might make a male change the quality of his ejaculate? For this we need a REAL MALE. A titan. A marvel of virility and a masculine inspiration for men everywhere!
(What, you were expecting a tiger or something? Via Wikpedia)
Cornwallis and Birkhead. “Changes in Sperm Quality and Numbers in Response to Experimental Manipulation of Male Social Status and Female Attractiveness.” The American Naturalist, 2007.